Fluid delivery device

ABSTRACT

A fluid delivery device ( 1 ) for discharging a fluid comprises a housing ( 2, 3 ), piston pump ( 4 ), biasing mechanism ( 5, 101 ), and trigger mechanism ( 6 ); the housing ( 2, 3 ) comprising a basal end ( 3 ) and discharge end ( 2 ) having an outlet ( 10 ) for discharging the fluid; the piston pump ( 4 ) comprising a casing ( 20 ) defining a pump chamber ( 35 ) for fluid storage, piston ( 21 ) slidably movable relative to the pump chamber ( 35 ), piston plunger ( 22 ), and delivery channel ( 59 ) for delivering fluid discharged from pump chamber ( 35 ) to outlet ( 10 ); the trigger mechanism ( 6 ) being movable from cocked configuration, preventing transfer of biasing mechanism ( 5, 101 ) force to the casing ( 20 ) to prevent casing ( 20 ) movement towards the outlet ( 10 ), to triggered configuration, enabling transfer of biasing mechanism ( 5, 101 ) force to the casing ( 20 ) to cause casing ( 20 ) movement towards the outlet ( 10 ) to discharge fluid from the pump chamber ( 35 ). The biasing mechanism ( 5, 101 ) comprises one or more flexible catch members ( 104 ) which in cocked configuration are catched and in triggered configuration are decoupled from the housing ( 2, 3 ). The trigger mechanism ( 6 ) comprises a manually movable button ( 100 ) at the housing basal end ( 3 ) comprising an obstructer ( 114 ) that in cocked configuration engages the catch members ( 104 ) to prevent decoupling.

The present disclosure relates to a fluid delivery device. Inparticular, it relates to a fluid delivery device for nasal, sub-lingualor ophthalmic use.

Fluid delivery devices are well known for dispensing media such aspowders and fluids for discharge into or onto the body. EP1219356discloses one such device in which a piston pump is used for discharginga flowable media from a reservoir out of an outlet nozzle for nasaldelivery. To operate the device a user manually displaces upwardly thereservoir relative to a support surface to cause a needle to form anopening in a sealing piston of the reservoir. Further manual movement ofthe reservoir by the user displaces the piston within the reservoir topressurise the flowable media and cause it to be discharged via theneedle.

WO2004/069664 discloses a closure member suitable for use in fluiddelivery devices having a piston pump. The closure member does notrequire piercing by a needle. Instead one or more resilient projectionson the closure member are used to seal a storage container. On actuationmanual displacement of the closure member relative to the storagecontainer causes the one or more resilient projections to deformaccommodating outflow of fluid from the storage container.

In both cases the devices rely on manual displacement of at least onepart of the piston pump for operation. This can lead to inconsistentdischarge of media from the devices. Reasons include the differentimpulses and loads applied to the piston pump by different users and thepossibility that a user will not fully complete the required stroke ofthe piston pump before releasing the device.

WO03/074189 describes a fluid dispensing device having a body housing apump action discharge device. Dispensing is controlled using a lockingmeans comprising detents engagable with apertures in a side wall of ahousing. However, disengaging the locking means while holding the nasalpiece in a nostril is awkward due to the location of the detents in theside wall. In particular, since the locking means is located remote fromthe nasal piece the user's fingers cannot be placed at the outlet end ofthe device on either side of the nasal piece such that one finger abutsagainst the nasal septum in use to reliably seat the nasal piece thecorrect distance into the user's nostril. In addition, squeezing twodetents together that are under a strong spring force requires a levelof force that may be difficult for elderly or infirm users.

According to the present disclosure there is provided a fluid deliverydevice for discharging a fluid comprising:

-   -   a housing;    -   a piston pump;    -   a biasing mechanism; and    -   a trigger mechanism;    -   the housing comprising a basal end and a discharge end having an        outlet for discharging the fluid;    -   the piston pump comprising a casing defining a pump chamber for        storage of the fluid, a piston slidably movable relative to the        pump chamber, a piston plunger, and a delivery channel for        delivering fluid discharged from the pump chamber to the outlet        of the housing;    -   the trigger mechanism being movable from a cocked configuration        to a triggered configuration;    -   in the cocked configuration the trigger mechanism prevents        transfer of a biasing force of the biasing mechanism to the        casing to thereby prevent movement of the casing towards the        outlet of the housing;    -   in the triggered configuration the trigger mechanism enables        transfer of the biasing force to the casing to thereby cause        movement of the casing towards the outlet of the housing so as        to discharge fluid from the pump chamber, along the delivery        channel and out of the outlet of the housing;    -   characterised in that the biasing mechanism comprises one or        more flexible catch members which in the cocked configuration        are catched to the housing and in the triggered configuration        are decoupled from the housing; and wherein the trigger        mechanism comprises a manually movable button located at the        basal end of the housing, the button comprising an obstructer        that in the cocked configuration engages the one or more        flexible catch members to prevent decoupling of the one or more        catch members from the housing.

Advantageously, the operation of the fluid delivery device is simple andconsistent. The use of the trigger mechanism in combination with thebiasing mechanism results in a predictable loading and impulse beingapplied to the casing of the piston pump. In addition, the deviceensures that the piston pump undergoes a full discharge stroke under theaction of the biasing mechanism. As such, partial discharges areprevented.

Preferably the button is movable along a longitudinal axis of the devicebetween the cocked and triggered configurations.

Preferably the biasing mechanism comprises a spring biasing the one ormore catch members towards the triggered configuration.

Preferably the one or more catch members and the housing compriseinter-engaging surfaces that in the cocked configuration urge the catchmembers to flex and decouple from the housing, wherein the position ofobstructer in the cocked configuration prevents said flexure.

The inter-engaging surfaces may comprise inclined surfaces on the catchmembers. The inclined surfaces may comprise one or more chamfers orradiused corners of the catch members.

Preferably the button comprises an inwardly directed projectioncomprising an enlarged head at a distal end, wherein the enlarged headcomprises the obstructer.

The one or more flexible catch members may comprises a plurality offlexible legs depending from a body portion, each flexible legcomprising a catch portion at a distal end. In which case, in the cockedconfiguration the catch portions may be located around the enlarged headof the obstructor and axially aligned therewith.

The button may comprise, or be coupled to, a narrow body below theobstructer and the button is movable into the triggered configuration bymovement away from the basal end into the housing so as to slide theenlarged head of the obstructor within the flexible legs to bring thenarrow body into alignment with the catch portions. The narrow body maybe integrally formed with a remainder of the obstructor and simplycomprise a portion of the obstructor of reduced external diameter.

The button may comprises a body portion and a projecting portion formedfrom different materials; wherein the body portion may be formed from arelatively flexible material and the projecting portion may be formedfrom a relatively stiff material. Advantageously, this allows theproperties of each part of the button to be optimised.

The projecting portion may comprise the obstructor. It is desirable toform the obstructor from a relatively stiff material such aspolypropylene that is adequately able to resist the inwardly-directedforce applied by the one or more catch members.

The body portion of the button may form a collapsible member. By using arelatively flexible material, such as a thermoplastic elastomer, thebody portion can be configured to be relatively easily collapsed. It isdesired that in the cocked configuration the body portion has sufficientinherent stiffness to retain its shape (which may be substantiallycup-shaped) but that in the triggered configuration it is easilydeformed by the biasing force to allow movement of the obstructor.Advantageously, using a relatively flexible material for the bodyportion of the button results in significantly less noise on operation.This is because there is no forceful face-to-face impact between hardplastic parts of the button and the housing.

The slide member may comprise the one or more flexible catch members.Alternatively, the one or more flexible catch members may be integrallyformed with the casing.

The slide member may comprise a recess for receiving and, optionally,abutting against the casing.

Preferably the piston comprises a body and at least one resilientprojection to seal the pump chamber in the cocked configuration; whereinon movement of the casing towards the outlet of the housing in thetriggered configuration, the at least one resilient projection isdeflectable due to the resultant increase in pressure within the pumpchamber so as to accommodate discharge of fluid from the pump chamberinto the delivery channel.

Preferably the at least one resilient projection extends around only aportion of a circumference of the piston.

Preferably at least one sealing projection axially aligned with the atleast one resilient projection extends round a remainder of thecircumference of the piston.

In one embodiment the slide member may be configured, in the triggeredconfiguration, to transfer the biasing force to the casing of the pistonpump. The slide member may transfer the biasing force to the casing bydirect contact therebetween.

In another embodiment the obstructor may be configured, in the triggeredconfiguration, to transfer the biasing force to the casing of the pistonpump. The obstructor may transfer the biasing force to the casing bydirect contact therebetween.

In the cocked configuration one or more assembly gaps may be presentbetween components of the device, for example, the piston plunger andthe piston, wherein the obstructor may be configured to be of asufficient length such that, starting from the cocked configuration,initial movement of the button may cause the obstructor to contact anddisplace the casing and piston to close any said assembly gaps, prior todecoupling of the one or more catch members from the housing. This isadvantageous in further reducing the operating noise of the device. Ithas been found that, where the force is transferred to the casing via aseparate slide member, the presence of assembly gap(s) in the device canlead to impact noises during triggering as, for example, the pistonplunger and piston are rapidly brought into contact with each otherunder the biasing force. By using the obstructor itself to transfer theforces, the assembly gap(s) may be closed relatively slowly during themanual movement of the button (including the obstructor) as theobstructor itself can bring all of the components into face-to-facecontact before the release of the one or more catch members transfersthe biasing force to the casing of the piston pump.

The button may be at least partially deformable such that in thetriggered configuration the button is retained in a visibly deformedstate to provide a visual indication to a user that the device has beenactivated.

The piston and the piston plunger may be fixed relative to the housing.

The device may be a single-use device.

There is also provided a fluid delivery device as described abovecombined with a single dose of fluid contained in the pump chamber. Thefluid may contain a pharmaceutical.

The term pharmaceutical, as used herein, is intended to encompass anypharmaceutical, compound, composition, medicament, agent or productwhich can be delivered or administered to a human being or animal, forexample pharmaceuticals, drugs, biological and medicinal products.Examples include antiallergics, analgesics, bronchodilators,antihistamines, therapeutic proteins and peptides, antitussives, anginalpreparations, antibiotics, anti-inflammatory preparations, hormones, orsulfonamides, such as, for example, a vasoconstrictive amine, an enzyme,an alkaloid, or a steroid, including combinations of two or morethereof. In particular, examples include isoproterenol[alpha-(isopropylaminomethyl)protocatechuyl alcohol], phenylephrine,phenylpropanolamine, glucagon, adrenochrome, trypsin, epinephrine,ephedrine, narcotine, codeine, atropine, heparin, morphine,dihydromorphinone, ergotamine, scopolamine, methapyrilene,cyanocobalamin, terbutaline, rimiterol, salbutamol, ipratropium bromideand salbutamol, flunisolide, colchicine, pirbuterol, beclomethasone,orciprenaline, fentanyl, and diamorphine, streptomycin, penicillin,procaine penicillin, tetracycline, chlorotetracycline andhydroxytetracycline, adrenocorticotropic hormone and adrenocorticalhormones, such as cortisone, hydrocortisone, hydrocortisone acetate andprednisolone, insulin, cromolyn sodium, and mometasone, includingcombinations of two or more thereof.

The pharmaceutical may be used as either the free base or as one or moresalts conventional in the art, such as, for example, acetate,benzenesulphonate, benzoate, bicarbonate, bitartrate, bromide, calciumedetate, camsylate, carbonate, chloride, citrate, dihydrochloride,edetate, edisylate, estolate, esylate, fumarate, fluceptate, gluconate,glutamate, glycollylarsanilate, hexylresorcinate, hydrobromide,hydrochloride, hydroxynaphthoate, iodide, isethionate, lactate,lactobionate, malate, maleate, mandelate, mesylate, methylbromide,methylnitrate, methylsulphate, mucate, napsylate, nitrate, pamoate,(embonate), pantothenate, phosphate, diphosphate, polygalacturonate,salicylate, stearate, subacetate, succinate, sulphate, tannate,tartrate, and triethiodide, including combinations of two or morethereof. Cationic salts may also be used, for example the alkali metals,e.g. Na and K, and ammonium salts and salts of amines known in the artto be pharmaceutically acceptable, for example glycine, ethylenediamine, choline, diethanolamine, triethanolamine, octadecylamine,diethylamine, triethylamine,1-amino-2-propanol-amino-2-(hydroxymethyl)propane-1,3-diol, and1-(3,4-dihydroxyphenyl)-2 isopropylaminoethanol.

The pharmaceutical will typically be one which is suitable for nasalinhalation and may be provided in any suitable fluid form for thispurpose, for example as a solution or powder suspension in a solvent orcarrier liquid, for example ethanol, or isopropyl alcohol. Thepharmaceutical may alternatively be one suitable for sub-lingual orophthalmic delivery.

The pharmaceutical may, for example, be one which is suitable for thetreatment of asthma. Examples include salbutamol, beclomethasone,salmeterol, fluticasone, formoterol, terbutaline, sodium chromoglycate,budesonide and flunisolide, and physiologically acceptable salts (forexample salbutamol sulphate, salmeterol xinafoate, fluticasonepropionate, beclomethasone dipropionate, and terbutaline sulphate),solvates and esters, including combinations of two or more thereof.Individual isomers such as, for example, R-salbutamol, may also be used.The pharmaceutical may, for example, be one which is suitable for thetreatment of migraine. An example is sumatriptan. As will beappreciated, the pharmaceutical may comprise of one or more activeingredients, an example of which is flutiform. One or more surfactantsmay be included if desired.

The piston may be formed from an elastomer or thermoelastomer materialsuch as EPDM, polychloroprene, hydrogenated nitrile, butyl, halo-butyl,dynamically cross-linked EPDM/PP (Santoprene®), styrenic blockcopolymers or blends thereof. Other suitable materials includehigh-density polyethylene and low-density polyethylene The housing maybe formed from an engineering plastic such as polypropylene, HDPE, ABS,polyester or POM.

The casing of the piston pump may be formed from any suitable materialsuch as glass, cyclic olefin copolymer—an example being Topas® COCavailable from TOPAS Advanced Polymers GmbH, Frankfurt-Höchst, Germany,or liquid crystal polymer—an example being Zenite® LCP available fromDuPont, Wilmington, USA.

Components of the biasing mechanism, trigger mechanism and housing maybe formed from a suitable material having the necessary flexuralcharacteristics, such as polypropylene, HDPE, ABS, polyester or POM.

The present disclosure will now be described, by way of example only,with reference to the accompanying drawings in which:

FIG. 1 is a perspective view of a first nasal device according to thepresent disclosure;

FIG. 2 is a side elevation of the nasal device of FIG. 1;

FIG. 3 is a cross-sectional view of the nasal device of FIG. 1;

FIG. 4 is an enlarged view of a section of FIG. 3;

FIG. 5 is a cross-sectional view of a piston pump of the nasal device ofFIG. 1;

FIG. 6 is a perspective view of a piston of the nasal device of FIG. 1;

FIG. 7 is a cross-sectional view of a second nasal device according tothe present disclosure; and

FIG. 8 is a cross-sectional view of a third nasal device according tothe present disclosure.

In the following, the fluid delivery device will be described, by way ofexample only, as a device suitable for nasal delivery of fluid.

As shown in the accompanying FIGS. 1 to 6, a first nasal device 1comprises an upper housing 2, a lower housing 3, a piston pump 4, aspring 5 and a trigger mechanism 6.

The housing of the device is formed from two parts, the upper housing 2and the lower housing 3. The upper housing 2 and lower housing 3 connecttogether by means of a pair of co-operating formations 70 and 71 as bestshown in FIG. 3 which will be described further below. A lower rim 73 ofthe upper housing 2 and an upper rim 74 of the lower housing 3 interfacewith one another on assembly of the device 1. An optional additionalsnap-fit arrangement or ultrasonic weld may be provided at thisinterface if desired.

The housing defines an interior for containing the remaining componentsof the device 1. The upper housing 2 and lower housing 3 together definea side wall 13 of the housing, a base 16 and opposite the base a nasalpiece 11 which extends upwardly towards an outlet orifice 10 which isprovided at a distal end thereof. A longitudinal axis of the device 1runs from the base 16 to the outlet orifice 10. Shoulder portions 12 areprovided between the nasal piece 11 and side wall 13.

As best shown in the cross-sectional view of FIG. 3, the nasal piece 11is provided with a first tubular extension 15 which extends downwardlyfrom an upper end of the nasal piece 11 towards the interior of thedevice 1. In addition, a second tubular extension 80 extends downwardlyfrom the shoulders 12 towards the base 16. A plurality of strengtheningwebs 81 are provided at an upper end of the second tubular extension 80.Towards a lower end of the second tubular extension 80 are located twoapertures 70 on opposite sides thereof. The bottom end of the secondtubular extension 80 is open.

The base 16 of the device 1 comprises a recess 90 formed by a thirdupwardly extending tubular extension 91 of the lower housing 3. Thethird tubular extension 91 has a stepped configuration with a relativewide lower part 92 and a relatively narrow upper part 93 joined togetherby a flange 95 having an outer portion in which two apertures 94 areprovided to allow access by mould tools during manufacture and aninwardly extending portion which defines a central aperture 96. A raisedannular ridge 120 is provided on an inner face of the third tubularextension 91.

The trigger mechanism 6 comprises a button 100 and slide 101.

The button 100 comprises a body formed from an inner transverse flange111 and an outer transverse flange 110 joined together by an X-shapedweb structure 112. The button 100 is provided with a projection 113having a relatively slim body that extends inwardly from the innerflange 111 and terminates in an enlarged head 114. As best shown in FIG.4, the distal end 115 of the head 114 is dome-shaped and an inclinedshoulder 116 is formed at the junction between the head 114 and the bodyof the projection. A lower face of the flange 110 forms a triggersurface that can be contacted in use by a finger or thumb of a user.

The slide 101 comprises a ring portion 102 and three dependent legs 103.The ring portion 102 is annular and has an inwardly directed shoulder118 at a base of a recess, the use of which will be described below. Thelegs 103 extend downwards and each terminate in an enlarged catchportion 104. As best shown in FIG. 4, each catch portion 104 comprisesan inwardly directed projection 117 and an outwardly directed projection119. An outer edge of the catch portion 104 is provided with a downwardfacing chamfer 106. An inner edge of a lower face of the projection 117is provided with a downward facing chamfer 105. An outer edge of anupper face of the projection 119 is provided with an upward facingchamfer 107.

The piston pump 4 is shown in FIG. 5 and comprises a container 20, apiston 21 and a plunger 22.

The container 20 comprises a generally cylindrical body 30 which has aclosed base 32 at one end and an upper opening 31 at an end opposite thebase 32. The container 20 defines a pump chamber 35 in which in use afluid may be stored prior to discharge on operation of the device 1.

The piston 21 comprises a piston body 40 which is shown in more detailin FIG. 6. The piston body 40 is generally cylindrical but is providedwith a number of shaped zones and projections for carrying out variousfunctions. Three resilient projections 41 are provided spaced apartaxially along the lower half of the piston body 40. Each resilientprojection 41 extends circumferentially around a portion of thecircumference of the piston body 40. The resilient projections 41 extendthrough an arc of approximately 100 degrees. The resilient projections41 are relatively deep in the radial direction and this relatively largeradial depth of the projections 41 renders them relatively flexiblecompared to the other sealing formations described below. The pistonbody 40 is further provided with three sealing projections 42 which areeach axially aligned with one of the resilient projections 41 and areformed as a circumferential extension of the outward radial edge of theresilient projections 41. Each of the sealing projections 42 extendround the remainder of the circumference of the piston body 40 notcoincident with the sector of the resilient projections 41. Thus eachsealing projection 42 extends round an arc of approximately 260 degrees.The sealing projections 42 extend radially slightly beyond the outersurface of the piston body 40. Since the ‘depth’ in the radial directionof the sealing projections 42 is relatively small compared to the depthof the resilient projections 41 they are relatively much less flexible.

The piston body 40 further comprises three sealing rings 43 provided atan upper end of the piston body 40 spaced axially apart from oneanother. In between the sealing rings 43 and the resilient projections41 is provided an inlet port 46 which, as shown in FIG. 5, communicateswith a transverse conduit within the interior of the piston body 40. Thetransverse conduit in turn communicates with an axially oriented axialconduit 45 which extends upwardly through the upper half of the pistonbody 40 and terminates at an outlet port 47 as shown in FIG. 6. The useof the inlet port 46 and outlet port 47 will be described further below.The upper face of the piston body 40 is provided with a circumferentialrecess 48 which is shaped to sealingly mate with the lower face of theplunger 22 as shown in FIG. 5.

The plunger 22 comprises a lower plunger portion 50 and an upper plungerportion 51 which are engaged with one another on assembly. If desiredthe engagement may be made permanent by use of a snap-fit formation orthrough welding or other adhesive mechanisms. The lower plunger portion50 comprises a generally cylindrical tubular component having acentrally extending bore 54. A lower end of the bore 54 communicateswith an inlet 53 which is provided at a centre of the lower end face ofthe plunger 22. The lower face of the lower plunger portion 50 isprovided with a circumferential ridge 52 shaped to matingly engage insealing manner with the circumferential recess 48 of the piston body 40.A plurality of axially extending strengthening ribs 56 extend up aportion of the exterior surface of the lower plunger portion 50 as shownmost clearly in FIG. 5.

The upper plunger portion 51 comprises a generally cylindrical componenthaving a narrower plug portion 57 at a lower end and a wider upperportion 62 at an upper end. On assembly as shown in FIG. 3, the plugportion 57 is received within the bore 54 of the lower plunger portion50 to define a lower portion 55 of a delivery channel which is annularin shape and lies between the internal surface of the lower plungerportion 50 and the exterior surface of the plug portion 57. As shown inFIG. 5, the upper portion 62 is provided with three spacers 58 whichabut against an upper edge of the lower plunger portion 50. The spacers58 act as standoffs to create three radial ports 60 that connect theinner portion 55 of the delivery channel to an upper portion 59 of thedelivery channel which is formed, as shown in FIG. 3, between anexterior face of the outer plunger portion 51 and an inner face of thetubular extension 15 of the upper housing 2. This outer portion 59 ofthe delivery channel comprises three axially extending paths that aredefined by grooves formed in the surface of the outer plunger portion51. Each groove extends from a respective port 60 upwardly to the upperend of the plunger portion 22. A swirl chamber formation 61 is providedat the upper end of the plunger 22.

The device 1 is assembled as follows. The container 20 is filled with adose of a desired fluid and the piston 21 is inserted. The plunger 22 isinserted into the tubular extension 15 of the upper housing 2 so thatthe swirl chamber 61 abuts against the outlet orifice 10. The spring 5and then the slide 101 are inserted through the open upper end of thelower housing 3 into the tubular extension 93. A lower end of the spring5 comes to rest on the inner portion of the flange 95. As the slide 101reaches the full insertion point the chamfer 106 on the outer edge ofthe catch portions 104 contacts the flange 95 causing the legs 103 todeflect towards each other enabling the catch portions 104 to passthrough the aperture 96. Once past the flange 95, the legs 103 springback into there original configuration. When fully inserted the ringportion 102 of the slide 101 has contacted and compressed the spring 5as shown in FIG. 3. Due to the chamfer 107 on the catch portions 104,the upward biasing force of the spring 5 on the slide 101 has the effectof wanting to pull the catch portions 104 back through the aperture 96.However this is prevented by inserting the button 100 into the tubularextension 92 of the lower housing 3 such that the head 114 is receivedin the aperture as shown in FIG. 3 at a location where the head 114contacts the inwardly directed projections 117 which prevents the legs103 deflecting towards one another. In this position the outer flange110 is abutted against a lower side of the annular ridge 120 on thetubular projection 92. The button 100 is retained in the cavity 90 bycontact between the annular ridge 120 and the inner transverse flange111.

The container 20 and piston 21 are now inserted into the open upper endof the tubular projection 93 so that a lower end of the container restsagainst the shoulder 118 of the ring portion 102.

Finally, the upper housing 2 is located over the lower housing such thatthe tubular portion 93 slides upwards within the tubular portion 80until the upper housing 2 and lower housing 3 snap-fit together onengagement of the co-operating formations 70, 71. The inclined upperface 72 of the projections 71 enable the tubular projection 80 to flexsufficiently for the parts to be assembled but the flat lower face ofthe projections 71 prevents the parts thereafter being separated. Inthis assembled position, the piston 21 is brought into mating contactwith the lower end of the plunger 22 as shown in FIG. 3.

The fluid in the chamber 35 comprises a single dose of fluid to bedischarged. Typically, the fluid contains a pharmaceutical. Thepharmaceutical may be provided as a solution or powder suspension in asolvent or carrier liquid, for example ethanol, or isopropyl alcohol.

The device 1 is shown in FIG. 3 with a trigger mechanism (formed fromthe button 100 and the flexible legs 103 of the slide 101) in a cockedconfiguration in which a biasing mechanism (formed from the combinationof the spring 5 and the slide 101) is unable to transfer its biasingforce to the casing 20 so as to move the casing 20 upwardly.

To use the device 1, a user grips the device 1 between the base 16 andthe shoulder portions 12 and places the nasal piece 11 into a nostril.With a single finger or thumb the device 1 is moved into a triggeredconfiguration by pushing up on the trigger surface of button 100. Withsufficient pressure the transverse outer flange 110 is flexed and pushedpast the annular ridge 120 such that the enlarged head 114 moves upwardsand out of alignment with the catch portions 104. Once the thinner bodyof the projection 113 is aligned with the catch portions 104 the legs103 can flex together under the force of the spring 5 pushing up on thering portion 102 and the inclined contact between the chamfers 107 ofthe catch portions 104 riding over the inner edge of the aperture 96.Thus movement of the button 100 causes the slide 101 to be decoupledfrom the lower housing 3 and as a result the slide 101 moves rapidlyupwards under the force of spring 5 pushing the body 30 of the container20 with it.

Due to the fact that the plunger 22 and piston 21 are fixed axiallyrelative to the upper housing 2, the upward movement of the body 30 ofthe container 20 has the corresponding effect of trying to reduce thevolume of the pump chamber 35 which results in pressurisation of thefluid within the pump chamber 35. This increase in the pressure of thefluid within the pump chamber 35 causes the resilient projections 41 todeflect upwardly allowing passage of the pressurised fluid between theresilient projections 41 and the inner face of the body 30 of thecontainer 20. Thus, the pressurised fluid is enabled to reach the inletport 46 of the piston body 40. The passage of fluid is only enabledthrough the 100 degree sector where the resilient projections 41 arelocated due to the relatively stiffer sealing performance of the sealingprojections 42 around the remainder of the circumference of the pistonbody 40. In addition, pressurised fluid cannot escape fully out of thepump chamber 35 other than via inlet port 46 due to the higher sealingperformance of the sealing rings 43.

Thus, pressurised fluid exits the pump chamber 35 through inlet port 46,along transverse conduit, along axial conduit 45 and out of outlet port47 of the piston body 40. Due to the fact that the outlet port 47 of thepiston body 40 is aligned with the inlet 53 of the plunger 22, thepressurised fluid enters the lower portion 55 of the delivery channeland is discharged upwardly between the lower plunger portion 50 and theplug portion 57 of the upper plunger portion 50. Thereafter, thepressurised fluid passes through the ports 60 into the upper portion 59of the delivery channel between the upper portion 62 and the tubularextension 15. Finally, the pressurised fluid reaches the swirl chamberformation 61 where the fluid is forced into a rotational swirl patternbefore exiting the outlet orifice 10 in the form of a spray.

The device 1 is preferably a disposable, single use device.

A second nasal device according to the present disclosure is shown inFIG. 7. In the following, only those differences between this device andthe preceding embodiment will be described. In all other aspects, thedevice 1 is of the same form and functions in the same manner as thefirst device. Consequently, like reference numerals are used in theFigures for like parts.

The button 200 of the second device 1 differs from the first device. Thebutton 200 comprises two parts, a cup-shaped body 201 and a projectingpart.

The body 201 comprises a bottom 210 and a lateral side wall 211. Theside wall 211 is provided with projections 215 at its distal end whichengage with the apertures 94 of the tubular extension 91. The bottom 210is provided with an aperture 202 in which is located the projectingpart. The body 201 does not comprise an equivalent to the inner flange111 of the first device.

The projecting part comprises a relatively slim body 213 that extendsinwardly from the bottom 210 and terminates in an enlarged head 214. Thedistal end of the head 214 is dome-shaped and an inclined shoulder 216is formed at the junction between the head 214 and the body of theprojection.

A lower face of the bottom 210 forms a trigger surface that can becontacted in use by a finger or thumb of a user. Preferably, the triggersurface may also comprise a flange 217 of the projecting part.

Preferably, the body 201 is formed from a thermoplastic elastomer (TPE)or other suitably flexible, resilient material. The projecting part isformed from a relatively rigid material such as polypropylene (PP). Thebody 201 and projecting part may be connected in any suitable manneralthough a preferred option is to form the button as a comoulding.

The body 201 is flexible to allow movement of the projecting partwithout disconnection of the body 201 from the tubular extension 91 ordisengagement of the projections 215 from the apertures 94. Movement ofthe projecting part is accommodated by deflection or deformation of theside wall 211 and/or bottom 210, for example by folding, bending orstretching of the material.

In use, the device 1 is moved from the cocked configuration of FIG. 7into the triggered configuration by pushing up on the trigger surface ofbutton 200, causing the projecting part to move upwards. The body 201flexes to accommodate the upwards movement of the projecting part. Asthe projecting part 213 moves upwards, the enlarged head 214 also movesupwards and eventually out of alignment with the catch portions 104.Once the thinner body 213 of the projecting part is aligned with thecatch portions 104 the legs 103 can flex together under the force of thespring 5 pushing up on the ring portion 102 and the inclined contactbetween the chamfers 107 of the catch portions 104 riding over the inneredge of the aperture 96. Thus movement of the projecting part causes theslide 101 to be decoupled from the lower housing 3 and as a result theslide 101 moves rapidly upwards under the force of spring 5 pushing thebody 30 of the container 20 with in the same manner as described withreference to the first device.

The use of the resilient button 200 reduces the noise produced duringoperation of the device, in particular because the button 200 does notcomprise an inner flange that is brought forcefully into contact withthe flange 95 of the housing.

The first and second devices 1 may comprise assembly gaps betweencomponents. Examples are a gap 350 which may be present between thelower plunger portion 50 and the piston 21 and a gap (not shown) betweenthe container 20 and the slide 101. These assembly gaps can beadvantageous to ensure that during manufacture and assembly of thedevice the piston 21 is not inadvertently moved within the casing 20which could lead to premature leakage of product. The presence of thegaps thus eases manufacture and assembly. However, during actuation ofthe device 1 the assembly gaps are rapidly closed during movement of thecomponents under the force of the biasing spring. The resulting impactsbetween the components may result in the generation of noise which maybe undesirable for the user. A third device 1 as shown in FIG. 8 seeksto overcome this potential disadvantage.

In the following, only those differences between the third device andthe second device will be described. In all other aspects, the device 1is of the same form and functions in the same manner as the seconddevice. Consequently, like reference numerals are used in the Figuresfor like parts.

The button 300 comprises two parts, a cup-shaped body 301 and aprojecting part.

As before, the body 301 comprises a bottom 310 and a lateral side walland is substantially the same and formed from the same materials as inthe second device. Two variations may be noted. Firstly, the side wallis not provided with projections at its distal end. Secondly, anenlarged mount 331 is provided for the projecting part to create astronger connection between the body 301 and the projecting part. Asbefore, the parts are preferably comoulded together.

The relatively slim body 313 of the projecting part is substantially asbefore. However the enlarged head 314 is significantly elongated suchthat it extends up and into the immediate vicinity of the bottom of thecasing 20. Only a small assembly gap 330 may be provided therebetween ifdesired.

An inclined shoulder 316 is again formed at the junction between thehead 314 and the body of the projecting part.

The housing is also modified in the vicinity of the spring 5 byproviding an inner tubular extension 393 inside the tubular extension 93which creates an annular chamber 395 therebetween. The inner tubularextension extends upwardly from the flange 95 which closes of the lowerend of the annular chamber 395. The spring 5 is located within theannular chamber 395.

In use, the device 1 is moved from the cocked configuration of FIG. 8into the triggered configuration by manually pushing up on the triggersurface of button 300, causing the projecting part to move upwards. Thebody 301 flexes to accommodate the upwards movement of the projectingpart.

The initial upward movement of the projecting part 313 causes the distalend of the enlarged head 314 to contact the lower end of the casing 20by closing the assembly gap 330 (if present). Next the upward movementmoves the casing 20 and piston 21 (as one) upwards to bring the piston21 into contact with the lower plunger portion 50, thus closing theassembly gap 350. It should be noted that the assembly gaps are closedduring the relatively slow manual movement of the button 300. Thereforeno, or little, noise is produced during this stage.

As the projecting part is moved manually further upwards, the enlargedhead 314 also moves upwards and eventually out of alignment with thecatch portions 104 as before. Once the thinner body 313 of theprojecting part is aligned with the catch portions 104 the legs 103 canflex together under the force of the spring 5 to engage the projectingpart under the shoulder 316. At this point the slide 101 is decoupledfrom the lower housing 3 and as a result the slide 101 can move rapidlyupwards under the force of spring 5. During this movement the legs 103are constrained to remain inwardly flexed due to the internal diameterof the inner tubular extension 393 against which the catch portions 104slide. Consequently, the biasing force of the spring 5 acting on theslide 101 is transferred via the catch portions 104 and the shoulder 316to the projecting part of the button 300. Thus, the biasing force isapplied to the casing 20 via the enlarged head 314 of the button 300 andnot via just the slide 101. Since the assembly gaps of the device areclosed prior to the slide 101 being decoupled, the activation noise issignificantly reduced. Activation noise is also reduced by the presenceof the inner tubular extension 393 as it helps to prevent recoil and‘snaking’ of the spring 5 which may occur where a larger void space isprovided surrounding the spring.

The third device 1 is configured such that the slide 101 moves apredetermined actuation distance on actuation of the device. The innertubular extension 393 has a length equal to or greater than thisactuation distance. As a result, after actuation, the legs 103 areretained within the bore of the inner tubular extension with the catchmembers still engaged under the shoulder 316. This prevents the button300 moving back downwards. This is advantageous in that it acts as avisible indicator that the device has been actuated and provides astable post-actuation structure in which the components are not free tobe rattled about.

While the description of the third device above describes the enlargedelongate head 314 directly contacting the container 20, it will beappreciated that the closure of the assembly gaps may also be achievedby indirect contact through an intermediate component between theprojecting part and the casing 20. For example, the elongate head 314may be formed from two or more pieces that are moved in turn.

The invention claimed is:
 1. A fluid delivery device for discharging afluid comprising: a housing; a piston pump; a biasing mechanism; anobstructor; and a trigger mechanism; the housing comprising a basal endand a discharge end, the discharge end having an outlet for dischargingthe fluid; the piston pump comprising a casing defining a pump chamberfor storage of the fluid, a piston slidably movable relative to the pumpchamber, a piston plunger, and a delivery channel for delivering fluiddischarged from the pump chamber to the outlet of the housing; thetrigger mechanism being movable from a cocked configuration to atriggered configuration; in the cocked configuration, the obstructorprevents transfer of a biasing force of the biasing mechanism to thecasing to thereby prevent movement of the casing towards the outlet ofthe housing; in the triggered configuration the trigger mechanismenables transfer of the biasing force to the casing to thereby causemovement of the casing towards the outlet of the housing so as todischarge fluid from the pump chamber, along the delivery channel andout of the outlet of the housing; wherein the biasing mechanismcomprises one or more flexible catch members which, in the cockedconfiguration, are catched to the housing and in the triggeredconfiguration are decoupled from the housing; wherein, in the cockedconfiguration, the obstructor engages the one or more flexible catchmembers to prevent decoupling of the one or more catch members from thehousing; and wherein the trigger mechanism comprises a button that ismanually movable to the triggered configuration to displace theobstructor and permit the one or more flexible catch members to decouplefrom the housing.
 2. The fluid delivery device as claimed in claim 1wherein the button is movable along a longitudinal axis of the devicebetween the cocked and triggered configurations.
 3. The fluid deliverydevice as claimed in claim 1 wherein the biasing mechanism comprises aspring biasing the one or more catch members towards the triggeredconfiguration.
 4. The fluid delivery device as claimed in claim 1wherein the one or more catch members and the housing compriseinter-engaging surfaces that, in the cocked configuration, urge thecatch members to flex and decouple from the housing, wherein theposition of obstructor in the cocked configuration prevents saidflexure.
 5. The fluid delivery device as claimed in claim 4 wherein theinter-engaging surfaces comprise inclined surfaces on the catch members.6. The fluid delivery device as claimed in claim 1 wherein the buttoncomprises, or is coupled to, an inwardly directed projection comprisingan enlarged head at a distal end, wherein the enlarged head comprisesthe obstructor.
 7. The fluid delivery device as claimed in claim 6wherein the one or more flexible catch members comprises a plurality offlexible legs depending from a body portion, each flexible legcomprising a catch member at a distal end.
 8. The fluid delivery deviceas claimed in claim 7 wherein, in the cocked configuration, the one ormore catch members are located around the enlarged head of theobstructor and axially aligned therewith.
 9. The fluid delivery deviceas claimed in claim 8 wherein the button comprises, or is coupled to, anarrow body below the obstructor and the button is movable into thetriggered configuration by movement away from the basal end into thehousing so as to slide the enlarged head of the obstructor within theflexible legs to bring the narrow body into alignment with the one ormore catch members.
 10. The fluid delivery device as claimed in claim 1wherein the button comprises a body portion and a projecting portionformed from different materials; wherein the body portion is formed froma relatively flexible material and the projecting portion is formed froma relatively stiff material.
 11. The fluid delivery device as claimed inclaim 10 wherein the projecting portion comprises the obstructor. 12.The fluid delivery device as claimed in claim 10 wherein the bodyportion of the button forms a collapsible member.
 13. The fluid deliverydevice as claimed in claim 1 further comprising a slide member whichcomprises the one or more flexible catch members.
 14. The fluid deliverydevice as claimed in claim 13 wherein the slide member comprises arecess for receiving and, optionally, abutting against the casing. 15.The fluid delivery device as claimed in claim 13 wherein the slidemember is configured, in the triggered configuration, to transfer thebiasing force to the casing of the piston pump.
 16. The fluid deliverydevice as claimed in claim 15 wherein the slide member transfers thebiasing force to the casing by direct contact therebetween.
 17. Thefluid delivery device as claimed in claim 1 wherein the obstructor isconfigured, in the triggered configuration, to transfer the biasingforce to the casing of the piston pump.
 18. The fluid delivery device asclaimed in claim 17 wherein the obstructor transfers the biasing forceto the casing by direct contact therebetween.
 19. The fluid deliverydevice as claimed in claim 17 wherein in the cocked configuration, oneor more assembly gaps are present between components of the device, andthe obstructor is of a sufficient length such that, starting from thecocked configuration, initial movement of the button causes theobstructor to contact and displace the casing and the piston to closesaid one or more assembly gaps prior to decoupling of the one or morecatch members from the housing.
 20. The fluid delivery device of claim 1wherein the button is at least partially deformable such that in thetriggered configuration the button is retained in a visibly deformedstate to provide a visual indication to a user that the device has beenactivated.
 21. The fluid delivery device of claim 1 wherein the pistonand the piston plunger are fixed relative to the housing.
 22. The fluiddelivery device of claim 1 wherein the device is a single-use device.23. The fluid delivery device of claim 1 combined with a single dose offluid contained in the pump chamber.
 24. The fluid device of claim 19wherein said one or more assembly gaps include an assembly gap betweenthe piston plunger and the piston.